diff options
Diffstat (limited to 'Lib/asyncio/tasks.py')
| -rw-r--r-- | Lib/asyncio/tasks.py | 36 |
1 files changed, 24 insertions, 12 deletions
diff --git a/Lib/asyncio/tasks.py b/Lib/asyncio/tasks.py index f5de1a2..a3a0a33 100644 --- a/Lib/asyncio/tasks.py +++ b/Lib/asyncio/tasks.py @@ -230,7 +230,7 @@ class Task(futures._PyFuture): # Inherit Python Task implementation """ return base_tasks._task_print_stack(self, limit, file) - def cancel(self): + def cancel(self, msg=None): """Request that this task cancel itself. This arranges for a CancelledError to be thrown into the @@ -254,13 +254,14 @@ class Task(futures._PyFuture): # Inherit Python Task implementation if self.done(): return False if self._fut_waiter is not None: - if self._fut_waiter.cancel(): + if self._fut_waiter.cancel(msg=msg): # Leave self._fut_waiter; it may be a Task that # catches and ignores the cancellation so we may have # to cancel it again later. return True # It must be the case that self.__step is already scheduled. self._must_cancel = True + self._cancel_message = msg return True def __step(self, exc=None): @@ -269,7 +270,8 @@ class Task(futures._PyFuture): # Inherit Python Task implementation f'_step(): already done: {self!r}, {exc!r}') if self._must_cancel: if not isinstance(exc, exceptions.CancelledError): - exc = exceptions.CancelledError() + exc = exceptions.CancelledError('' + if self._cancel_message is None else self._cancel_message) self._must_cancel = False coro = self._coro self._fut_waiter = None @@ -287,11 +289,15 @@ class Task(futures._PyFuture): # Inherit Python Task implementation if self._must_cancel: # Task is cancelled right before coro stops. self._must_cancel = False - super().cancel() + super().cancel(msg=self._cancel_message) else: super().set_result(exc.value) - except exceptions.CancelledError: - super().cancel() # I.e., Future.cancel(self). + except exceptions.CancelledError as exc: + if exc.args: + cancel_msg = exc.args[0] + else: + cancel_msg = None + super().cancel(msg=cancel_msg) # I.e., Future.cancel(self). except (KeyboardInterrupt, SystemExit) as exc: super().set_exception(exc) raise @@ -319,7 +325,8 @@ class Task(futures._PyFuture): # Inherit Python Task implementation self.__wakeup, context=self._context) self._fut_waiter = result if self._must_cancel: - if self._fut_waiter.cancel(): + if self._fut_waiter.cancel( + msg=self._cancel_message): self._must_cancel = False else: new_exc = RuntimeError( @@ -716,12 +723,12 @@ class _GatheringFuture(futures.Future): self._children = children self._cancel_requested = False - def cancel(self): + def cancel(self, msg=None): if self.done(): return False ret = False for child in self._children: - if child.cancel(): + if child.cancel(msg=msg): ret = True if ret: # If any child tasks were actually cancelled, we should @@ -780,7 +787,8 @@ def gather(*coros_or_futures, loop=None, return_exceptions=False): # Check if 'fut' is cancelled first, as # 'fut.exception()' will *raise* a CancelledError # instead of returning it. - exc = exceptions.CancelledError() + exc = exceptions.CancelledError('' + if fut._cancel_message is None else fut._cancel_message) outer.set_exception(exc) return else: @@ -799,7 +807,9 @@ def gather(*coros_or_futures, loop=None, return_exceptions=False): # Check if 'fut' is cancelled first, as # 'fut.exception()' will *raise* a CancelledError # instead of returning it. - res = exceptions.CancelledError() + res = exceptions.CancelledError( + '' if fut._cancel_message is None else + fut._cancel_message) else: res = fut.exception() if res is None: @@ -810,7 +820,9 @@ def gather(*coros_or_futures, loop=None, return_exceptions=False): # If gather is being cancelled we must propagate the # cancellation regardless of *return_exceptions* argument. # See issue 32684. - outer.set_exception(exceptions.CancelledError()) + exc = exceptions.CancelledError('' + if fut._cancel_message is None else fut._cancel_message) + outer.set_exception(exc) else: outer.set_result(results) |